nodejs equivalent of java's phaser synchronization barrier

Node.js provides an equivalent of Java's Phaser synchronization construct through the worker_threads module. In Node.js, Phaser-like behavior can be achieved using a combination of Worker threads, MessageChannel, and other synchronization primitives such as Promise, AsyncFunction, or custom implementations.

Here's a simplified example demonstrating how you can achieve Phaser-like synchronization using worker_threads in Node.js:

// main.js
const { Worker, MessageChannel } = require('worker_threads');

class Phaser {
  constructor(numWorkers) {
    this.numWorkers = numWorkers;
    this.barrier = new MessageChannel().port1;
    this.workers = [];
  }

  arriveAndAwait() {
    return new Promise(resolve => {
      const worker = new Worker('./worker.js');
      this.workers.push(worker);

      worker.postMessage({ barrier: this.barrier }, [this.barrier]);

      worker.once('message', () => {
        resolve();
      });
    });
  }

  async waitForCompletion() {
    await Promise.all(this.workers.map(worker => {
      return new Promise(resolve => {
        worker.once('message', () => {
          resolve();
        });
      });
    }));
  }
}

const phaser = new Phaser(3);

async function run() {
  for (let i = 0; i < 3; i++) {
    await phaser.arriveAndAwait();
    console.log(`Worker ${i + 1} has completed phase.`);
  }

  await phaser.waitForCompletion();
  console.log('All workers have completed all phases.');
}

run();

// worker.js
const { parentPort } = require('worker_threads');

parentPort.once('message', (message) => {
  const barrier = message.barrier;

  setTimeout(() => {
    // Simulate some work being done by the worker
    console.log('Worker completed its task.');

    // Signal that the worker has completed its task
    barrier.postMessage(null);
  }, Math.random() * 3000);
});

In this example:

main.js creates a Phaser class that emulates Phaser-like behavior. It creates a pool of worker threads and synchronizes their execution using message passing.
Each worker thread (worker.js) waits for a message from the main thread, then simulates some work and signals back to the main thread upon completion.

This implementation demonstrates how you can achieve Phaser-like synchronization in Node.js using worker_threads and message passing. Depending on your specific requirements, you may need to extend or customize this implementation further.

preveen-stack / nodejs

nodejs equivalent of java's phaser synchronization barrier #31